1. Field of the Invention
The present invention relates to a battery system for a vehicle, and particularly, to a battery system for a hybrid vehicle or an electric vehicle.
2. Description of the Related Art
Some hybrid and electric vehicles released in recent years differ in the configuration in which a battery module to be mounted and a junction box which for connecting the battery module to other electronic components are disposed. For example, Japanese Unexamined Patent Application Publication No. 2007-299593 (hereinafter referred to as JP-A No. 2007-299593) discloses a hybrid vehicle having a configuration in which a center console box between the driver's seat and the assistant driver's seat is provided with a battery pack assembly, and a junction box is disposed on top of the battery pack assembly.
However, when a junction box is disposed on top of the battery module as in the configuration of the technology disclosed in JP-A No. 2007-299593, there is a problem in that the height of the center console box tends to increase, and thus it is difficult to effectively use the space inside the vehicle, for example, by disposing a case, in which the junction box and the battery module are disposed, below the luggage compartment at the rear of the vehicle. Now, an approach may be taken in which the junction box is disposed not on top of the battery module, but at the side of the battery module in the case so as to reduce the height of the case. However, when the junction box and the battery module are fixed to respective surfaces with different heights and vibration is transmitted to the junction box and the battery module, the vibration causes a relative positional difference between the junction box and the battery module, and thus a busbar which connects between the junction box and the battery module may be damaged. When the junction box is directly fixed to the case, operating noise or vibration due to a relay or the like in the junction box is transmitted to the case and further amplified, so that loud noise may be transmitted to the vehicle cabin. In order to prevent such an event, it is necessary to increase the thickness of the plate of the case, and/or provide a reinforcing member. However, this increases the weight of the case and the cost. Replacing the busbar with a more flexible one also increases the cost, and allowing relative motion between the junction box and the battery module in this manner involves a corresponding amount of reserved space in consideration of the relative motion, and thus the space to be reserved may increase.